Intuitive feel

From apm
Jump to: navigation, search

This is an introduction to the character of robotic work in the nanocosm.
It should deliver some intuitive feeling of how things work down there.

Atoms

  • How big is an atom?

"Atoms are unimaginably small." that is very a common belief. And whenever some comparison is brought up one usually feels confirmed on hat assumption. But it turns out that there is a "best way" to get an intuitive feel for their size that is rarely used (or never until here for the first time??). Here are the details: "Magnification theme-park". – Judge for yourself whether this "atoms are unimaginably small" belief is false misbelief after all.

  • How does it feel when you grab two atoms and rub them against each other?
    Atoms are very soft and slippery.
    Main article: "The feel of atoms"
  • How do atoms work and what shape do they have?
    They work like vibrating drums, just different in all the details.
    Their shape is like symmetric smooth clouds, a bit like blurred fruit seeds. Shape can change when neighbor atoms change.
    Main article: "The basics of atoms"
  • At which speeds do Atoms usually move?
    Too fast to find an intuitive way to imagine it. Sorry.
    The Speed of sound (experienced half a million times faster if you scale up to barely see the model-atoms).
    But an intuitive feeling for speeds will be attainable for motion of bigger stuff that is of more interest (namely crystolecules).
    Main article: "The speed of atoms"

Speeds

  • At which speeds do Atoms usually move?
    See answer above in section Atoms.
    Main article: "The speed of atoms"
  • At which speeds will nanorobotics usually operate?
    Pretty slow actually. In the low mm/s range.
    (experienced pretty fast if you scale up to barely see the model-atoms. About mach 7)
    Main article: "The speed of nanorobotics"

Everything is "magnetic"

Well, it's not really magnetism, but magnetism seems to be the best macroscale analogy for getting across a basic intuitive feeling. When going down to the nanoscale one encounters a new force that is omnipresent always and everywhere. The Van der Waals force (VdW). It feels as if everything where magnetic. Everything and anything loose will stick to everything else that it comes too close to.

  • Similar to the magnetic force we are used to in everyday macroscale life, the VdW force drops off very quickly with distance / is rather short in range.
    More short range even than magnetism - (TODO: verify quantitatively - low importance)
  • Unlike a magnetic force the VdW force has no polarity. Is always attractive. Well, when things come close enough there's repulsion from nonbonded interactions.
    (Also related are some means for levitation).

The VdW force is extremely useful for putting and holding stuff together at the nanoscale (and maybe microscale). Temporarily during (dis)assembly or permanently in final products.
Even small amounts of contact area can make a bond that is strong enough such that the relentless eternal jostling of thermal motion for all practical purposes never suffices to kick loose even one of many mols of parts. For more details see: Connection method#Van der Waals locking.

Of course from the actual physical origins (and the quantitative effects) the magnetic force and the VdW force are very much different. So instead of everything is "magnetic" it would be better to say that everything is "vanderwaalic".

Side-note:
Instead of using the magnetic force as commonly known macroscale analogy an alternative macroscale analogy would be everything is "sticky". This alternate analogy is not used here mainly because:

  • stickiness is usually associated with some sort of glue and thus with high viscosity which absolutely does not match reality even as a superficial analogy. Magnetism on the other hand is not associated to any medium and is associated with extremely low friction.
  • Magnetism (just as the VdW force) noticeably increases in strength when closing in. Glue does not really behave that way.

Everything is extremely bouncy

Drop some macroscale machine part like e.g. a metal gear down at a metal surface and it quickly comes to rest. Not so much at the nanoscale. Crystolecules behave more like rubber balls, just worse. Way worse. Rubber balls that just do not want to stop bouncing.

Side-note: In some situations (like e.g. a flat disk hitting a flat wall) nanoscale gemstone "bouncyness" can become involved into a serious fight with nanoscale gemstone "vanderwalicness". Working out who wins (bounce-back or snap-to) is a serious mathematical/physical modeling challenge. Experiments are needed, but many of those can't be done yet.

That bounciness is not only present when you smash a crystolecule against a wall, but also (which is more relevant) in the operation of gemstone based nanomachinery. Flex waves can run back and forth, barely damped, long ways through complex and even branched axle systems.

While designing for this can be major PITA (ahem pretty difficult) like in electrical circuit design, it also potentially offers the possibility to archive extreme high efficiencies.

Also one can gain more control via deliberate introduction of discrete damping elements.

Everything is shaky

Worse than in a wood wheeled carriage racing over cobblestones.
Or: You are like an astronaut – don't ever let go of your tools – they may haunt you

  • What happens when you let go of a building block?

Main article: "The heat-overpowers-gravity size-scale"

Let's consider an somewhat unusual fall experiment. A small gripper let go of a building block. Simple? See if you answer right.

Related: spiky needle grabbing

A fall experiment quiz to illustrate the quite unfamiliar mechanical behavior in the nanoscale.

Scaling laws

They describe what changes when one goes down the scale. E.g. that magnetic motors become weak but electrostatic ones strong. More details can be found at the scaling laws main page.

The prospective feel of gem-gum products

Gem-gum products though machine like robotic in the nanocosm are not necessarily cold hard and robot like to the human senses (See: Soft-core macrorobots with hard-core nanomachinery). Emulated elasticity can create any form imaginable with gradients from soft to hard. It isn't an easy to attain property but it is an highly desirable one and will emerge at some point.

Related

Provide means for an intuitive understanding seems to be a good didactic approach for a wide target audience.

In the book "Radical Abundance"

In the book Radical Abundance the introduction tries to convey an intuitive feel for how things behave down at the nanoscale. (wiki-TODO: give a more precise reference)

Richard Feynman

There are great recordings of the famous physicist and teacher Richard Feynmen about the importance:

  • of an intuitive understanding of things and
  • of looking at things from new perspectives.

Main article: Richard Feynman

Related

Getting a good intuition about atoms

For an intuitive understanding how energies, forces, and stiffness
at the nanoscale compare to each other see: Energy, force, and stiffness

Getting a good intuition about thermal motions

Averting false intuitions – things that may come unexpected

Truely intuitively understanding the size scales involved

An intuition about the possible consequences of gemstone metamaterial technology

External links